Oil-tank



(No Model.)

W. H. BIRGE.

Oil Tank.

No. 234,745. Patented- Nov. 23,1880.

INVENTOR ATTORNEY TATES Nrrn ATENT @rrrcn.

OIL-TANK.

SPECIFICATION formingpart of Letters Patent No. 234,745, dated November'23, 1880,

Application filed September 11, 1880. (No model.)

To all whom it may concern:

Be it known that'I, WILLIAM H. BIRGE, of Franklin, in the county of Venan go and State of Pennsylvania, have invented certain new and useful Improvements in Oil-Tanks; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference bein ghad to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

My invention relates to an improvement in oil-tanks. In order to prevent the accidental ignition and consequent destruction of large quantities of crude oil stored in tanks, (from twenty-five to thirty thousand barrels of crude oil being stored in a single tank,) it is necessary that the tanks shall be covered, and hence the ordinaryplan of construction is to place asheetmetal roof over the tank, the roof being supported on posts-resting on the bottom of the tank. This plan or form of construction is open to avery serious objection for the following reason: Gas escaping from the large surface of oil in the tank accumulates beneath the sheet-iron roof. The latter, being made to extend above the top of the tank, forms a space above the top of the oil for the storage of the escaping gas. It is often the case that oil-tanks are struck by lightning, and when lightning strikes a tank constructed in the manner above set forth the large quantity of gas stored beneath the roof is instantly ignited and exploded, the explosion either throwing the roof off from the tank or shivering it in pieces, thus exposing the oil and setting it on fire. The result of such au'accident is the loss of the great quantity of oil stored in the tank and the destruction of the tank itself, which alone involves a loss of several thousands of dollars.

The object of my invention is to provide an oil-tank of such description that the surface of oil in the tank will always be covered and protected, regardless of the quantity of oil in the tank, and no space he provided between the oil and cover for the accumulation of the escapin g gases; and with these ends in view my invention consists, essentially, in an oiltank, the combination, with a floating cover,

perforated and having guide-tubes registering with said perforations, of posts passing through said guide-tubes and resting on the bottom of the oil-tank, and a roof secured to the upper ends of said posts.

In the accompanying drawings, Figure 1 is a view, in vertical section, of an oil-tank constructed in accordance with my invention,and Fig. 2 is a plan view of the floating cover.

A represents the storing-tank, which may be of any desired size, form, and of any approved construction.

B is the cover, the top a of which is nearly as large as the tank, sufficient space being provided between the edge of the cover and inner surface of the tank to allow the cover to have a free and unrestricted vertical movement. Cover B is provided with a flange, I), which extends upwardly from the top a around its edge. When oil is pumped into the tank the coveris floated on the top of the oil and rises until the tank is filled. Oil will rise between the tank and flange and form a thin annular body of oil, which serves as a liquid seal, preventing the possible entrance of flame below the cover. WVhen the oil is pumped from the tank the cover descends to the bottom.

Thus it will be seen that the oil in the tank is always provided with a cover irrespective of the quantity of oil in the tank, and that under no circumstances can gas accumulate.

The onlybody of oil that can possibly become ignited is the thin annular body between the upwardly-projecting flange b of the cover and the tank, and should such body of oil become ignited it could be readily extinguished, and would probably go out for lack of sufficient oil to support combustion.

The cover a is further provided with a number of perforations, 0, each of said perforations being provided with a guide-tube, E, which latter are equal in length to the height of the flange 1). Posts F are passed through the guidetubes E and perforations c and rest on the bottom A of the oil-tank. Roof A is supported on the upper ends of the posts F.

It is to be observed that the posts F do not in any way interfere with the free and unrestricted movement of the cover B in the tank.

It is evident that slight changes in the construction and arrangement of parts might be claim as new, and desire to secure by Letters self to the exact construction and arrangement resorted to Without departing from the spirit on the bottom of the oil-tank, and a roof seof my invention, and hence I do not limit mycured to the upper ends of said posts substantially as setforth.

In testimony that I claim the foregoing I 15 have hereunto set my hand this 7th day of September, 1880.

of parts shown and described.

Having fully described my invention, What I Patent, isa In an oil-tank, the combination, with a floating cover, perforated, and having guide-tubes registering with said perforations, of posts passing through said guide-tubes and resting l WILLIAM H. BIRGE.

Witnesses GEORGE ALLEN, G. W. BRIGHAM. 

